Some conventional automatic summarization techniques can automatically create a summary of a document which includes important sentences and phrases from the document. Users can then view the summary in order to quickly learn what the document is about without reading the entire document. However, creating a summary that is separate from the document itself carries a high risk if it is wrong. For example, failure to include an important sentence in a summary may completely alter the user's understanding of the document because the user is not presented with all of the important information. As such, failure to include even one important sentence may greatly decrease the accuracy of the summary. Furthermore, because such summaries are often read instead of the document itself, errors in the summary may not be detected.